Funders worried about climate change have a lot on their plates, including waging a war on coal, saving the Amazon, and pushing China to develop in a sustainable way. Well, here's another high-stakes corner of the climate fight that's attracting grant money: curbing methane gas emissions.

Methane is the second-most common greenhouse gas emitted in the United States, accounting for about 10 percent of all greenhouse gas emissions from human activities. It is also produced by natural sources, such as a byproduct of bacteria-induced decay of organic matter. The primary human causes of methane emissions include raising livestock or leaking natural gas systems. Although methane doesn’t last as long in the atmosphere as carbon dioxide,the primary greenhouse gas, methane is better at trapping solar radiation. According to the Environmental Protection Agency, the impact of methane on climate change is 25 times greater than carbon dioxide over a 100-year period.

Yet, the amount of methane gas released has been severely underestimated, according to a study published in April 2014 in the Proceedings of the National Academy of Sciences—up to 1,000 times more methane is released at natural gas wells than the EPA has estimated.

This year, the White House announced that through executive action, it would impose a 40 to 45 percent reduction of methane pollution from the oil and gas industry by 2025. The initiative was met with industry and political hostility. Five prominent GOP Senators, led by James Inhofe Chairman of the Senate Committee on the Environment and Public Works wrote a letter to President Obama, saying the new regulations are ”unnecessary and will… slow domestic energy production.” According to Mother Jones, Inhofe has received more money from Koch Industries—one of the biggest privately held companies in the U.S.—than from any other source.

Meanwhile, on the other side of the fight, there are some significant environmental funders. Among these is the Hewlett Foundation, which has been supporting the Environmental Defense Fund (EDF) for its methane abatement work with a $3 million grant through 2016.

EDF is a leader on the methane issue among environmental groups. In 2012, it launched its largest research project to date to learn more about methane sources, and producing a series of studies in collaboration with almost 100 research and industry experts.

Work like this costs a lot of money, but EDF is one of the best-funded environmental groups around, with a budget of $134 million last year. It has a wide range of wealthy backers, including philanthropists we've written about often at IP: Carl Ferenbach, Julian Roberston, Stanley Druckenmiller, John Doerr, Stephen Mandel, and James Murdoch. (EDF's ties to some of these donors have generated controversy.) Many of these gifts come in the form of general operating support, which allows a place like EDF to spring big for research studies even if can't find dedicated support. EDF is also backed by a number of major foundations in addition to Hewlett, including the MacArthur, Moore, and Walton family foundations. This support has usually been restricted to specific projects.

It's not surprising that Hewlett would get behind the methane piece of EDF's work in a big way. The foundation has long been thinking about methane gas. For example, it backed a successful 2014 campaign to get Colorado to become the first state to regulate emissions of methane from oil and gas production activities. Grantees for that work included Conservation Colorado and Earthjustice, as well as EDF.

The $3 million grant to EDF, awarded last year, targets both local and national regulations building off successful work to regulate methane emissions in Texas and Colorado. Hewlett and EDF are looking for more wins at the state level, but have also kept an eye on the fight over methane that's heating up at the federal level.

EDF is tackling the petrochemical industry head-on, touting the methane abatement industry as a jobs creator, and commissioning an economic analysis that concluded “the 40% reduction is achievable while saving the U.S. economy and consumers over $100 million per year.”

As for the Obama administration's methane rules, this fight is ongoing, along with the battle over regulating greenhouse gas emissions from coal-fired plants—a fight, by the way, that Hewlett is also involved in.